P.O BOX 429, NUKU ALOFA, Tel: (676) Fax: (676)

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1 P.O BOX 429, NUKU ALOFA, Tel: (676) Fax: (676) February, 2015 Lord Dalgety Electricity Commission Tu atakilangi Nuku alofa Dear Lord Dalgety Re: Monthly Compliance Report January, 2015 In accordance with the reporting requirements of the Electricity Concession Contract and in response to your request for additional information as specified in the suggested MOU dated May, 2012, TPL submits the following reports for the month of January, System Loss Report 2. Fuel Efficiency Report 3. Reliability Measures Report (Tongatapu and Outer Islands) 4. Monthly Outage Events Report The above report items are described in detail below. 1. System Loss Report The following graphs illustrate the 12 months Moving Average (smoothed) Systems Losses for all four islands since July The 12 months moving average losses are used because of the variability of monthly Real Time Systems Losses due to the impact of the number of days and fall of the weekends in respect to meter reading cycle. In addition, system loss report is always one month late as last month consumption data (i.e. meter readings) will only be read this month and available to report next month. Hence January EC Report contains only December system loss data. 1

2 For the month of December, 2014, all island moving average system losses have decreased slightly from 12.55% (December, 2014) to 12.07% (January, 2014) but still achieve the regulatory target of 13%. The individual island group s system losses are shown below. The graph above shows that Tongatapu systems losses have decreased from 11.53% (November) to 12.06% (December). 2

3 Vava u losses however, have reduced from 12.78% to 12.37% (see the graph below). Ha apai system losses have always been below target until January, Since January, system losses have increased possibly due to Cyclone Ian effect. 3

4 Eua systems losses have been steady around 13% during past several months. 2. Fuel Efficiency Report It is important to note that fuel efficiencies calculated here include diesel deneration only (i.e. renewable generation has been excluded) as stipulated by the Electricity Concession Contract. Tongatapu fuel efficiency ratios have always been unachieved due to ageing generators and introudction of renewable generation plants that reduce diesel generators load factors. 4

5 Vava u fuel efficiency ratios have been well above the taregt due to the two new 600KW generators commissioned in May, Mostly, fuel efficiency ratios have been under achieved in Haapai but been steady in the last few months. 5

6 Mostly, fuel efficiency ratios have been under achieved in Eua. Overall, all island fuel efficiency ratios have been below the weighted average target of 4.17 KWh/L. 6

7 3. Reliability Measures (Tongatapu) Reliability Measures SAIDI Monthly Performance (Minutes) CAIDI Monthly Performance (Minutes) SAIFI Monthly Performance Month 2011/ / / /15 Month 2011/ / / /15 Month 2011/ / / /15 Jul Jul Jul Aug Aug Aug Sep Sep Sep Oct Oct Oct Nov Nov Nov Dec Dec Dec Jan Jan Jan Feb Feb Feb Mar Mar Mar Apr Apr Apr May May May Jun Jun Jun Total Total Total SAIDI minutes (measuring average total duration of interruption per connected customer) for the month of January, 2015 have increased significantly from (December, 2014) to (January, 2015) minutes (see the table above). Some of the major HV faults contributed to the SAIDI minutes for the month of January are described below. 7

8 Report Date No of Customers Off Fault Description Repair Comment 23/01/ ,432 Power off Feeder 1 and 2 was switch on at 09:30; feeder 3 was switched on at 09:35 30/01/ ,432 Power off Problem from the Power Station 31/01/ ,432 Power blackout 03/01/2015 4,106 On Feeder Vaini Power on for Feeder Vaini at 12:20 28/01/2015 4,106 Shut Down Feeder #1 16/01/2015 4,106 Shut Down 30/01/2015 4,106 Planned Shut down Matafonua,Fatai, Lakepa, Holoipepe. Replace HV pole at Pahu, finished at 02:30 then reconnect power on but Vaini feeer fell and part of Hihifo was still off 03/01/2015 4,106 On feeder Vaini Stand by at Popua Power on Feeder Vaini from Fua'amotu to Niutoua 12/01/2015 4,106 Power off to Vaini feeder 01:02 Feeder Vaini Feed back on except Malapo to Niutoua and also Halaliku 13/01/2015 4,106 Power off Switch on feeder 3 28/01/2015 1,489 Vaini's Feeder Drop Malapo ki niutoua 3:23 - time Vaini feeder was on 21/01/ A broken coconut tree was broke down HV line 03/01/ Low volts Materials: link 6A x 1 12/01/ Power off 13/01/ Power off Power shut down from Nautoka to Niutoua Kanokupolu, 'Utulau, Fahefa, Vaotu'u (places reported off) Two inline fuse blown 2 x 40A HV link replace. Inline fuse blown at Tokomololo; 15:58 - switch power on from Tokomololo to Ha'atafu Te'ekiu; 16:16 - switch power on from Maui to Nukunuku 17/01/ Power off Power off due to HRC fuse link was blown. Material use 25A x 1 HRC fuse link. Test After 238V 28/01/ Power off Materials: link 10A x 1 28/01/ Power off POWER OFF DUE TO 1 INLINE FUSE BLOWN SO THEY FIX IT THEN CONNECT POWER LINE WITH 1 x A 29/01/ Power off Materials: link 100A x 3 29/01/ Power off Materials: link 3A x 1 12/01/ Braker 01:10 Malapo to Fua'amotu feed back; 01:20 Malapo to Niutoua feed back 28/01/ High volts complaint Materials: IPC 16/95 x 2, gopher wire 1m; test before: R - 209V, B - 247V, Y - 261V; test after: R - 234V, B - 241V, Y - 240V [ loose neutral from main line ] 08/01/ Sparks Trimm tree branches; Line sparks due to tree branch too close and touching the HV line 02/01/ Trees on line Off 5:32; On 06:24 19/01/ Tree branch on HV line Remove coconut leaves from line 21/01/ Leaves in HV line Remove coconut leaves from HV line 22/01/ Tree leaves on line Repairs removed coconut tree leaves from HV line 22/01/ Tree leaves on line Remove coconut leaves from HV line 22/01/ Tree leaves on HV line Remove coconut Leaves from HV line 03/01/ Open inline fuse Open inline fuse from Pea 03/01/ Close inline fuse Close inline fuse from 'Atele 03/01/ Feeder Vaini drop again Feeder Vaini drop again at 12:38PmPower back on to normal 05:02Pm 13/01/ Power off 17/01/ Shut down 17/01/ Switch power line on Switch encloser at Malapo switch power on from Malapo to Niutoua and Haveluliku to Fatumu All of Fua'amotu's power was off. [ open DDO fuse for safety cross over container under H.V. lines from main road to Air port control tower ] Shut down power of Fua'amotu due to transfer container inside to the airport powers back on 16:20 28/01/ Power off Due to the shut down power was off from the recloser at Tokomololo, repair switch power on 8

9 Cumulative SAIDI YTD is showing below. The annual target is 5% less than the last year s value. CAIDI minutes (measuring average total duration of interruption per interrupted customer) for the month of December 2014 have however decreased from minutes (December, 2014) to minutes (January, 2015). Cumulative CAIDI YTD is showing below. The annual target is 5% less than the last year s value. 9

10 SAIFI (measuring average number of interruptions per customer) has increased significantly from (December, 2014) to 5.25 (January, 2015). Cumulative SAIFI YTD is showing below. The annual target is 5% less than the last year s value. 4. Reliability Measures (Outer Islands) Since July 2014, TPL collects outage data to calculate the reliability measures for all three outer islands. The accumulated measures are shown below graphically. The above graph shows the accumulated SAIDI for all three islands since July, The SAIDI figures include both planned and unplanned outages. Haapai has the highest SAIDI minutes in December due to large planned outages during Cyclone Ian reconstruction project. Planned SAIDI figures were found very high compared with the unplanned SAIDI figures. 10

11 Accumulated CAIDI figures are high for Ha apai due to planned outages. Again, planned CAIDI figures were found very high for all three islands compared with the unplanned CAIDI figures. Cumulative SAIFI figures were found significantly high for Vavau compared with Eua and Ha apai, implying that Vavau has higher number of outages than the other two islands. 11

12 5. Monthly Outage Events Fault Events Comparison 2014 vs YTD Total Planned/Unplanned Outage Events Jul-13 Jul-14 Aug-13 Aug-14 Sep-13 Sep-14 Oct-13 Oct-14 Nov-13 Nov-14 Dec-13 Dec-14 Jan-14 Jan-15 Feb-14 Feb-15 Mar-14 Mar-15 Apr-14 Apr-14 May-14 May-15 Jun-14 Jun / /15 Generator problem HV Lines HV/LV Transformer HV Pole LV Lines Service lines Customer premises Street Lights Meter Total There were total of 580 planned outages & unplanned fault events for the month of January, 2015 affecting 81,792 customers (it is possible that the same customer would have been affected by outages more than once). As per the table above, the number of fault events has slightly decreased from 612 in December, 2014 to 580 events in January, Number of faults in all categories has decreased from the last month. Most of the customer services faults included fuses at the service line tap off point for a premise. Should you have any queries with the information provided, please do not hesitate to contact me. Yours Faithfully, Ajith Fernando Risk & Compliance Manager Tonga Power Limited 12